1. Field of the Invention
The present invention relates to an apparatus and a facility for treating dirty water.
2. Description of the Related Art
Presently, no satisfactory methods have been developed for treating dirty water of aquariums, rivers, lakes and marshes, bays, and home sewage.
In an aquarium tank, a water treatment apparatus such as a filter unit is disposed above the tank and/or at the bottom of the tank. However, fish sometimes die due to deteriorated quality of water caused by food and excretions of fish. Therefore, conventional aquariums require frequent changes of water and careful cleaning techniques.
In large scale water treatment facilities, water is circulated to undergo physical filtration with a fibrous filter, and germs and algae in the water are suppressed (the genes of algae are broken down) by ultraviolet rays and ozone, thereby cleaning the water. Also, containers including activated carbon have been buried in the bottom of a river for cleaning the river water.
Contamination of water in rivers, lakes and marshes in areas functioning as a source for a water supply has created a serious social problem. In areas where algae are excessively produced due to overnourishment of water, mud is contaminated as a result of accumulation and decomposition of chlorellas so that deterioration of water quality has progressed.
In addition, since hygienic flush toilets have been introduced not only in urban areas but also in farming areas, construction and improvement of sewer systems and sewage treatment plants have been demanded. Moreover, deterioration of the natural environment is thought to progress because of inflow of home sewage into rivers in areas where sewer systems and sewage treatment plants are not provided, the habit of disposing of body wastes into the environment together with water, and destruction of the natural water cleaning system.